CN101047411A

CN101047411A - Fast adaptive power control for a variable multirate communications system

Info

Publication number: CN101047411A
Application number: CNA2006101007592A
Authority: CN
Inventors: J·W·海姆
Original assignee: InterDigital Technology Corp
Current assignee: InterDigital Technology Corp
Priority date: 2000-07-26
Filing date: 2001-07-12
Publication date: 2007-10-03
Also published as: US6832095B2; US20110081941A1; US20020027959A1; US9084200B2; BR0113022A; KR20100003300A; NO336899B1; HK1060220A1; CN100578956C; HK1099142A1; ES2193897T3; US20070117583A1; DE01952673T1; CN100589338C; KR20110018394A; IL193218A; ATE338387T1; KR20030096384A; KR100842239B1; NO328536B1

Abstract

A system and a method of controlling transmitter power in a wireless communication system in which user data is processed as a multirate signal having a rate N(t) and in which the user data signal having rate N(t) for transmission. The transmission power is adjusted on a relatively slow basis based on quality of data received by a receiver of the transmitted data. The transmitter power is determined as a function of N(t)/M(t) such that a change in the data rate in the multiple channels or the rate of the transmission data signal is compensated in advance of a quality of data based adjustment associated with such data rate change. Preferably, the user data signal having rate N(t) is converted into the transmission data signal having the faster rate M(t) by repeating selected data bits whereby the energy per bit to noise spectrum density ratio is increased in the transmission data signal.

Description

The quick self-adapted power control of variable multirate communication system

The application is that application number is 200510092459.X, and the applying date is July 12 calendar year 2001, and denomination of invention is divided an application for the Chinese invention patent application of " variable multirate communication system quick self-adapted power control ".

Technical field

The present invention relates to the power control of wireless communication system, specifically, i.e. the quick self-adapted power control system and the method for variable multirate communication system.

Background technology

The Poewr control method that the various wireless communication system is arranged known in the state of the art.A kind of example of the open Loop Power control transmitter system of single-rate data system as shown in Figure 1.A kind of example that the closed power of single-rate data controls transmitter system as shown in Figure 2.

The purpose of two kinds of systems is when decline propagation channel and time dependent interference occurring and reduces transmitter power to the full extent, guarantees that simultaneously the data that far-end receives have the acceptable quality.Usually, transmitter power is to change by the scale factor that changes to digital data in numeral is implemented, and for example, changes the gain of radio frequency amplifier on the contrary.

In existing state-of-the-art communication system, as third generation partnership projects (3GPP) time division duplex (TDD) and frequency division duplexing (FDD) system, a plurality of passages of variable-speed data are combined transmit.Fig. 3 and open loop and the closed power control transmission system that is respectively prior art shown in Figure 4.The background technology of this system requires data to check in 1.0 editions the 3rd volumes of third generation multisystem atmospheric interference specification requirement that 3GPP TS25.233 3.3.0 version, 3GPPTS25.222 3.2.0 version, 3GPP TS25.224 3.6 editions and radio industry commercial guild (ARIB) formulate, 1.0 revised editions.

The open loop of this adaptive multi-rate wireless communication system and closed loop power control system are slower to data rate variations response speed, and consequently performance is not the most desirable, and for example transmitting power is too high and received signal quality is low.Thereby necessary fast method and the system that a kind of changes in data rate adaptive power control is provided, to obtain perfect performance.

Summary of the invention

The invention provides a kind of method that controls transmitter power in the wireless communication system of controlling, wherein user data is as the how fast signal processing with rate N (t), and wherein user data signal is converted into the transmission of data signals with higher transmission rates M (t).Through-put power is the quality according to transmission data receiver received data, with lower rate adaptation.Transmitter power is pressed the function of N (t)/M (t) and is determined that corresponding adjusting is compensated according to this changes in data rate in advance thereby make the data rate of user data signal or the rate variations of transmission of data signals.By the data bit that repeats to select, speed is that the user data signal of N (t) preferably is converted to the transmission of data signals with higher rate M (t), and wherein energy per bit increases the noise spectrum density ratio in the transmission of data signals.

This method is applicable to open loop or the closed-loop control system that adopts scale factor to control transmitter power.No matter apply the present invention to have in the transmitter that open cycle system still is a closed-loop system, all preferably  (N (t)/M (t)) is applied to scale factor.

This method is applicable to that its transmitter receives the open Loop Power control system of a reference signal, reference signal power data, actual measurement interference power data and target sir (SIR) data, and wherein the foundation of SIR data is the received signal quality data of gathering with than low rate.Transmitter is measured interference signal and is determined the reference signal power that received, and according to reference signal power data that receives and the reference signal power determined, calculating path loss.Transmitter and then calculate scale factor according to actual measurement interference power data, target SIR and the  (N (t)/M (t)) of the path loss that calculates, reception.

This method also is applicable to rising/following drop data that utilization is produced by receiver and calculates the closed-loop system of scale factor according to rising/following drop data and  (N (t)/M (t)).Rising/following drop data preferably by receiver by from the actual measurement interference power data of transmitter received signal, and produce based on the method that the target sir (SIR) with the received signal quality data of gathering than low rate merges to small part.The target SIR data are preferably used based on the method that multiply by coefficient N (t)/M (t) with the nominal target SIR data than the received signal quality data of low rate collection and are calculated, and make the target SIR data be able to quick adjustment when data rate changes.

The present invention also provides a kind of wireless communication system transmitter, wherein user data is as the how fast signal processing with rate N (t), and wherein speed is that the user data signal of N (t) is converted into the transmission of data signals with higher transmission rates M (t).This transmitter through-put power is by to using the method for a scale factor based on the transmitter power of transmission data receiver received data quality, with lower rate adaptation.Transmitter contains a data-signal rate converter and is used for user data signal rate N (t) is increased to higher data transmission rate M (t), is used for part with a processor and comes the computes transmit power scale factor according to the data relevant with the received data quality that receiver produced.The data signaling rate transducer is associated with processor, make processor come the computes transmit power scale factor by the function of N (t)/M (t), wherein the rate variation of the data rate of user data signal or transmission of data signals is compensated according to corresponding adjusting of this changes in data rate in advance.

By the data bit that repeats to select, speed is that the user data signal of N (t) preferably is converted to the transmission of data signals with higher rate M (t), and wherein energy per bit increases the noise spectrum density ratio in the transmission of data signals.

Transmitter can be configured to the part of open Loop Power control system, wherein transmitter receives the transmission data from receiver: reference signal, reference signal power data, actual measurement interference power data and a target sir (SIR), wherein the foundation of SIR data is the received signal quality data of gathering with than low rate.Equally, transmitter contains one and is used to measure the signal measurement apparatus that receives reference signal power and is used for receiving reference signal power according to the reference signal power data that receives and actual measurement and come the treatment circuit of calculating path loss.Transmitter processor is according to the path loss of calculating, actual measurement interference power data, target SIR data and the  (N (t)/M (t)) of reception, computes transmit power scale factor.

Transmitter also can be configured to the part of closed loop power control system, and wherein transmitter receives the rising/following drop data that is produced by receiver.Equally, Transmitter processor is come the computes transmit power scale factor according to rising/following drop data and  (N (t)/M (t)).

The present invention also provides a kind of wireless communication system closed loop transmission power control system, wherein user data is as the how fast signal processing with rate N (t), and wherein speed is that the user data signal of N (t) preferably is converted to the transmission of data signals with higher rate M (t), and wherein through-put power is to regulate by the scale factor of application responds rising/following drop data.System contains a receiver that receives M (t) rate transmissioning data signal and produce rising/following drop data.Receiver preferably contains a data-signal rate converter, be used to reduce the data rate that receives the transmission data, produce one and have the user data signal of lower data rate N (t), a quality of data measurement mechanism of measuring the user data signal quality of data, and be used for part is calculated rising/following drop data according to actual measurement user data signal quality circuit.The pass of data signaling rate transducer and this circuit is, circuit calculates rising/following drop data by the function of N (t)/M (t), and wherein the rate variation of the data rate of user data signal or transmission of data signals is compensated according to corresponding adjusting of this changes in data rate in advance.

This system also preferably has been equipped with the transmitter that a data-signal rate converter is arranged, by the data bit that repeats to select, with speed is that the data-signal of N (t) is converted to the transmission of data signals with higher rate M (t), and wherein energy per bit increases the noise spectrum density ratio in the transmission of data signals.

In a preferred embodiment, receiver has adopted the interferometry device of the interfering signal power that a measurement receives with M (t) rate transmissioning data signal.Quality of data measurement mechanism is exported nominal target SIR data according to lower reception quality of data data.Receiver circuit is by an actual measurement interference power data from the transmitter received signal, method with the target sir SIR data merging that calculates by the method that nominal target SIR data be multiply by coefficient N (t)/M (t), calculate rising/following drop data, make the target SIR data when data rate changes, be able to quick adjustment.

According to following explanation to the at present preferable specific embodiment of the present invention, other purpose and advantage are conspicuous for the personnel that grasp this technical field basic fundamental.

Description of drawings

Figure 1 shows that the schematic diagram of traditional single-rate radio communication open Loop Power control system.

Figure 2 shows that the schematic diagram of traditional single-rate radio communication closed loop power control system.

Figure 3 shows that the schematic diagram of the how fast radio communication open Loop Power control of conventional variable system.

Figure 4 shows that the schematic diagram of the how fast radio communication closed loop power control system of conventional variable.

Figure 5 shows that the method that adopt to repeat with data rate from every 6 block diagrams that are converted to 8.

Figure 6 shows that and adopt the method that repeats that data rate is converted to 6 block diagram under every 8.

Figure 7 shows that schematic diagram according to the theoretical quick self-adapted open Loop Power control of the variable how fast radio communication system that makes of the present invention.

Figure 8 shows that schematic diagram according to the theoretical quick self-adapted closed loop power control system of making of variable how fast radio communication of the present invention.

Embodiment

The Poewr control method of conventional wireless system such as 3G PP adopts so-called internal loop and external loop-around.Looking internal loop is open loop or closed loop, and power control system is called as open loop or closed loop.And the external loop-around of two kinds of systems is closed loop.

The open-loop control system relevant portion that contains " emission " communication station 10 and " reception " communication station 30 as shown in Figure 1.

Communication station

10,30 is transceiver.Usually one of them is the base station, and another is the user equipment (UE) type.For clarity sake, the selected part of only having drawn among the figure.

A transceiver 11 is contained in cell site 10, wherein contains a data circuit 12 and is used for transmitting the transmission user data signal.User data signal provides with the power stage of expectation, and the through-put power ratio factor that the output 13 by application processor 15 is produced is regulated transmission power level.User data emits from the antenna system 14 of transmitter 11.

Containing the radio signal 20 of launching data is received by reception antenna system 31 by receiving station 30.The reception antenna system also can receive the interference radio signal 21 that influence receives the quality of data.An interference power measurement mechanism 32 is contained in receiving station 30, and received signal is as its input signal, and interference power data are surveyed in equipment 32 outputs.A data mass measurement equipment 34 is also contained in receiving station 30, and received signal is also as its output, and equipment 34 produces a data quality signal.Quality of data measuring equipment 34 and treatment facility 36 couplings, User Defined quality standard calculation of parameter target sir (SIR) data that treatment facility 36 received signal quality data and basis receive by input 37.

A transmitter 38 that is coupled with interference power measuring equipment 32 and target SIR generation processor 36 is also contained in receiving station.The transmitter 38 of receiving station also contains the

output

40,41,42 that is respectively applied for input user data, reference signal and reference signal transmit power data.Receiving station is by corresponding antenna system 39 its user data of emission and control relevant data and reference signal.

A receiver 16 and corresponding reception antenna system 17 are contained in cell site 10.The receiver 16 of cell site receives and contains the control signal that receiving station's user data 44 and receiving station 30 produced and the radio signal of data 45 by receiving station's 30 emissions.

Cell site's processor 15 is associated with cell site's receiver 16, in order to calculate the transmitting power scale factor.Transmitter 11 also comprises one and is used to measure the equipment 18 that receives reference signal power, and equipment 18 is associated with path loss calculation circuit 19.

For calculating the transmitting power scale factor, processor 15 receives the data from target SIR data input 22, wherein is loaded with target SIR data that produced by receiving station's target SIR generation processor 36; An interference power data input 23 wherein is loaded with interfering data and a path loss data input 24 of being produced by receiving station's interference power measuring equipment 32, wherein is loaded with the path loss signal that is produced by path loss calculation circuit 19.The path loss signal is to be produced from being loaded with from the reference signal transmit power data input 25 of the reference signal transmit power data of receiving station 30 and being loaded with the actual measurement reference signal power input 26 of reference signal power-measuring device 28 outputs of transmitter 11 by path loss calculation circuit 19.Reference

signal measuring equipment

18 and 39 couplings of cell site's receiver are being measured its power when receiving station's transmitter 38 receives reference signal.Path loss calculation circuit 19 is poor according to input 25 known reference power signal intensity that transmits and the actual measurement received power intensity of importing 26 transmission, has preferably determined path loss.

Interference power data, reference signal power data and target SIR value are sent to cell site 10 significantly to be lower than propagation channel and to disturb the speed of rate of change in time." interior " loop is that system relies on the part of measuring interface.System is regarded as " open loop " system, because not to provide feedback with propagation channel and the speed of disturbing rate of change in time to be complementary to algorithm, show that minimum needs the good and bad of transmitting power estimated value.Transmit power levels changes fast if desired, and system can not make corresponding response, in time regulates scale factor.

As for the external loop-around of open Loop Power control shown in Figure 1 system, at long-range receiving station 30 places, the quality of received signal is measured by measuring equipment 34.The module commonly used of digital data quality is bit error rate (BER) and piece error rate.The data of accumulating in the time period of time dependent propagation channel and interference period need significantly be longer than in the calculating of these values.For all given values, between value and reception SIR, there is certain theory relation.When the data of remote receiver accumulation are enough to assess this value, just calculate and compare, then the target SIR upgraded of output with desired magnitude (desired qualities of representative service) in the processor 36.The target SIR of upgrading is to be applied to the transmitter internal loop make measured value converge on (theory) value of desired value.The target SIR of upgrading is sent to transmitter 11 and uses for interior its loop by receiving station's transmitter 38 and cell site's receiver 16.The renewal rate of target SIR is accumulated statistic of attribute data required time and controlled transmitter the physical constraints that sends signal rate to power to be retrained.

Consult Fig. 2, for containing the communication system of cell site 50 and receiving station 70, wherein adopted closed loop power control system shown in the figure.

A transmitter 51 that is equipped with data circuit 52 is contained in cell site 50, and data circuit is used to transmit the user data signal that will transmit.User data signal provides with required power stage, regulates power stage by the transmitting power scale factor of using from processor 55 outputs 53.User data is by antenna system 54 emissions of transmitter 51.

Containing the radio signal 60 of launching data is received by reception antenna system 71 by receiving station.The reception antenna system also can receive the interference radio signal 71 that influence receives the quality of data.Interference power measuring equipment 72 is contained in receiving station 70, and received signal is imported as it, equipment 72 output actual measurement SIR data.A data mass measurement equipment 74 is also contained in receiving station 70, and received signal is also as its input, and equipment 74 has produced a data quality signal.Quality of data measuring equipment 74 and processor 76 couplings, User Defined quality standard calculation of parameter target sir (SIR) data that received signal quality data and basis receive by input 75.

Combiner 76 is preferably and is subtracter, will compare from the actual measurement SIR data of equipment 72 and the calculating target SIR data of from processor 74, and the most handy subtraction is exported a SIR error signal.SIR error signal from combiner 76 inputs to treatment circuit 77, and produces rising/decline order in view of the above.

A transmitter 78 that is coupled with treatment circuit 77 is also contained in receiving station 70.The transmitter 78 of receiving station also contains a user data with importing 80.Receiving station 70 is by corresponding antenna system 79 its user data of emission and the data relevant with control.

The corresponding reception antenna of a receiver 56 and one system 57 is contained in cell site 50.The receiver 56 of cell site receives the radio signal that contains the control data 85 of receiving station's user data 84 and receiving station's generation from receiving station 70.

The scale factor processor 55 of cell site has an input 58 related with cell site's receiver 16.Processor 55 receives the increase and decrease order and calculates the transmitting power scale factor in view of the above by importing 58.

As for the internal loop of closed loop power control system, the receiver 51 of cell site is adjusted its power according to " rising " and " decline " order that long-range receiving station 70 is produced.At long-range receiving station 70 places, by measuring equipment 72 measure the SIR that receives data and with compare by the target SIR value that processor 74 produces by combiner 72.The data that the target SIR value promptly receives in hypothesis can produce the value of desired service quality when containing this value.If actual measurement receives SIR less than target SIR, then send one " decline " order by the transmitter 78 of receiving station and the receiver 56 of cell site, otherwise will send one " rising " order by treatment circuit 77.Power control system is regarded as " closed loop " system, because the high-speed feedback of " rising " and " decline " order can be made real time reaction to time dependent propagation channel and interference.If change because of time dependent interference and propagation cause the expectation transmit power levels, it can make quick response and corresponding adjusting transmitting power.

As for the external loop-around of closed loop power control system, the quality that receives data is measured by measuring equipment 73 in receiving station.The module commonly used of digital data quality is bit error rate (BER) and piece error rate.The data of accumulating in the time period of time dependent propagation channel and interference period need significantly be longer than in the calculating of these values.For all given values, between value and reception SIR, there is certain theory relation.When the data of remote receiver accumulation are enough to assess this value, just calculate and compare, then the target SIR upgraded of output with desired magnitude (desired qualities of representative service) in the processor 74.The target SIR of upgrading is to be applied to receiver algorithm make measured value converge on (theory) value of desired value.The target SIR of upgrading is used further in the internal loop to determine that sending to cell site's power proportions produces rising or the decline order that processor 55 is used to control transmitter 51 power.

Illustrated in figures 1 and 2 is single-rate data transmission utilization measure control system.But in digital communication system, but the form of data piece also can be handled by given every amount of bits and given piece speed by given bit rate and given block size.In this system, for example 3GPPFDD and TDD system whenever all may have a plurality of data rates in the communication system, and this data rate may change in time.Figure 3 shows that a kind of transmission has the improved open Loop Power control of a plurality of data channel wireless systems system of variable data speed, Figure 4 shows that improved closed loop power control system.

For multichannel variable-speed data transmission is provided, open Loop Power control shown in Figure 1 system after improving as shown in Figure 3, wherein contain one in the cell site 10 upconverter 27 and the down-converter 47 in receiving station 30.

The user data of transmission is integrated with a signal with data rate N (t).Speed is that the data flow of N (t) is converted to the data flow that speed is M (t) by upconverter 27, and wherein transducer 27 contains one and is loaded with the output 28 that speed is the transmission of data signals of M (t).

At receiving station 30 places, speed be the user data signal of M (t) receive with transducer 47 and under be converted to original rate N (t).The interference of interference power measuring equipment 32 measuring-signal when receiving with higher speed M (t).Quality of data measuring equipment 34 is coupled with the user data path in transducer 47 downstreams, and is converted to N (t) the speed quality of measurement data afterwards under data.

For multichannel variable-speed data transmission is provided, closed loop power control system shown in Figure 2 after improving as shown in Figure 4, wherein contain one in the cell site 50 upconverter 67 and the down-converter 87 in receiving station 70.The user data of transmission is integrated with a signal with data rate N (t).Speed is that the data flow of N (t) is converted to the data flow that speed is M (t) by upconverter 67, and wherein transducer 67 contains one and is loaded with the output 68 that speed is the transmission of data signals of M (t).

At receiving station 70 places, speed be the user data signal of M (t) receive with transducer 87 and under be converted to original rate N (t).The interference of interference power measuring equipment 72 measuring-signal when receiving with higher speed M (t).Quality of data measuring equipment 73 is coupled with the user data path in transducer 87 downstreams, and is converted to N (t) the speed quality of measurement data afterwards under data.

In two kinds of multichannel variable bit rate systems, be provided for being transferred to the user data input of

remote receiver

30,70 for

transmitter

11,51, its data rate is the N (t) of mark, and the speed of exporting from the user data of remote receiver is also identical.Data rate N (t) can be made of several data rates of the different pieces of information passage of multiplex (MUX) in shared aggregate channel transmission.N is the function of (t), the expression speed can change in time, promptly this moment with at that time different, piece is different with piece.The reason that changes comprise data channel increase and (or) actual data rate changes in deletion and the existing passage, this is common in the packets of information service.

In Fig. 3 and two kinds of systems shown in Figure 4, data rate becomes M (t) from N (t) in transmitted data path, changes back to N (t) in remote receiver again equally.Data rate N (t) is a user data rate, and data rate M (t) then is a radio-communication data speed, and both may not the least concerned.

For example in 3GPP TDD system, M (t) is the bit number in per 10 milliseconds of frames under the situation of given timeslot number, and the orthogonal variable invasin is encoded with given invasin.M is the function of (t), and expression speed may change, and promptly this moment, more particularly, frame was different with frame with different at that time.Change M be equal to change invasin and (or) the employed physical channel of every frame number, change N and then be equal to changes in data rate in one or more data channel.Speed M (t) is equal to the N in per 10 milliseconds of frames _Data.jBit number, N (t) are equal in time t, when TFCj is effective, in per 10 milliseconds of frames

PL * 1 / {RM}_{\min} \underset{TrCHi}{Σ {RM}_{i}} * N_{ij}

Bit number, wherein according to defining among the 3GPP:

N _IjFor with combinations of transport formats j in TrCH i before the rate-matched, the bit number in radio frequency frame.

RM _iThe semi-static rate-matched attribute of TrCH i that sends as signal from higher level.

PL is for puncturing the limit, and this value is used to limit the puncture amount that can be applicable to reduce the physical channel number, and sends as signal from higher level.

N _Data.jIt is total bit number of the synthetic TrCH that can be used for having encoded with combinations of transport formats j in the radio frequency frame.

TF _i(j) be the TrCH i transformat of combinations of transport formats j.

TB or transmission block (Transport Block) are defined as the master data unit that exchanged before L1 and MAC.The equivalent terms of transmission block is " MAC PDU ".

TBS or transmission block collection are defined as the one group of transmission block that uses identical transformat to exchange simultaneously between the 1st layer and MAC.

TrCH or transmission passage carry out the passage that data transmit for what physical layer provided to the 2nd layer between the reciprocity ground floor entity that is marked.Dissimilar transmission passages is how to reach to transmit with which kind of characteristic to define on this physical layer according to data, for example, is to use dedicated physical channel also to be to use shared physical channel etc.

TF or transformat are defined as ground floor is provided for transmitting in certain transmission passage in certain Transmission Time Interval the transmission block collection to MAC form.Transformat is made of two parts---a dynamic part and a semi-static part.

TFC or combinations of transport formats are defined as all and transmit current effective transformat on the passage, comprise that promptly each transmits a transformat of passage.

TFCS or transport format combination set are defined as one group of combinations of transport formats.

MAC or media interviews controls (Medium Access Control) be the sublayer of the radio interface second layer, provide unacknowledged data transmission in the logical channel to serve and to the visit of transfer passage.

PDU or protocol data unit data unit for defining in (N) protocol layer, and by (N) Protocol Control Information and have (N) user data and constitute.

Be converted to M (t) from rate N (t) and the

transducer

26,27 of

cell site

10,50, carry out, the upward conversion that expression is undertaken by factor M (t)/N (t).Be converted to N (t) from speed M (t) and the

transducer

47,87 of receiving

station

30,70, carry out, represent following conversion by factor N (t)/M (t) carries out.

In Fig. 3 and two kinds of systems shown in Figure 4, visible speed M (t) is all greater than rate N (t).This is to have a mind to arrange.The upwards unconscious effect of rate transition occurs over just the situation that goes up conversion in the transmitter with the method that repeats, and reducing this situation is one of purpose of the present invention, will be described hereinafter.If N (t)=M (t) then this effect can not take place, if N (t)＞M (t) then effect is different, this is not a theme of the present invention.

The method that goes up the available repetition of conversion of data rate realizes, promptly repetition rate be position selected in the piece of N up to its contain with speed be in the piece of M bit number identical till, and merge repetition " soft " bit that receives with numeral and descend to change.Figure 5 shows that an example going up conversion with repetition methods, wherein increase to the situation that eight bits are simplified, B from every six bit for data rate _iBe i " firmly " bit in the input sequence, promptly ± 1.In this example, 2 and 5 two bits are repeated, and block size has been become eight from six.Figure 6 shows that the following transfer process that input is made of eight " soft " bits, wherein b _i+ n _jBe " soft " bit, that is, and the bit B of emission _iReceiver in the noise contribution n of a numeral sample when adding time j _j" soft "

bit

2 and 3 that receives carries out digital addition, forms

former bit

2 and 3 proportional modification; Similarly, " soft "

bit

6 and 7 of reception carries out digital addition, forms former bit 5 proportional modification.

The specific repetition bits of using in this example is represented the even distribution of repetition bits, with digital multiplexer as the specified scheme of using in the 3GPP system.But the selection of repetition bits and relation of the present invention are not close.

The method of above-mentioned data rate transition is the part with the what is called " rate-matched " of used repeat function in 3GPP TDD and the FDD system.This method is with respect to the advantage that transmission (being two in example) dummy bit changes the oversimplification method of data speed, can utilize can differ between the former longer piece of lacking and sending to improve signal quality.For clear for explanation in example, the energy that receives

bit

2 and 5 is other twice that receives bit to bit noise spectrum density ratio (Eb/No).Make the bit error rate (BER) and the piece error rate that receive data like this, with those repetition bits is not arranged and replace with the quality metric of the reception data of two dummy bits and compared comprehensive improvement.Certainly, only need the energy of six units, but used the energy emission data of eight units.Though the result is not intended to but consequence is the increase that has caused emitted energy, and cause the raising that receives the quality of data.These effects are solved by the present invention.

In fact the control system with single-rate data illustrated in figures 1 and 2 is identical with closed loop power control system with variable how fast data open loop shown in Figure 4 for Fig. 3.Fig. 3 and Fig. 4 represent the open loop and the closed loop power control system of 3GPP TDD communication system.But two kinds of power control systems of open loop and closed loop all owe desirable in the direction that influences that solves variable how fast changes in data rate.

In open cycle system shown in Figure 3, because N (t) equals the M (t) under the static state, ignore the modification of fading channel or any variable interference, target SIR will be stabilized in a quiescent point, obtain the desired data quality.This situation is equivalent to single-rate example shown in Figure 1.But in multichannel variable bit rate system, at certain time t, N and (or) M changes.As mentioned above, this situation can make the measured data quality metric improve, and the energy of emission is greater than the energy of actual needs.With the raising that loop finally can detect signal quality of locating, thereby reduce the target SIR of internal loop, reduce transmitter power, as to being considered as the compensation of too high signal quality than low rate operation.Meanwhile, transmitter 11 will use than actual needs more energy and launch data (making the reception of data can reach desired qualities).In the open Loop Power control cell site is under the situation (as the situation of 3GPP system) of battery powered mobile device, needs to consume unnecessary battery electric power.

Figure 7 shows that the present invention is applied to the open Loop Power control of variable how fast data, wherein corresponding element use with Fig. 3 in identical reference number mark.As shown in Figure 7, the transducer 27 of cell site has an extra input 29 that is input to scale factor generation processor 15.By importing 29, this transducer provides a signal that is equal to  (N (t)/M (t)) to processor 15, as the coefficient that calculates the transmitting power scale factor.Therefore, when the scale factor of revision is applied to transmit data, transmitting power is regulated at once by following coefficient:

(N(t)/M(t))

Rate variation with compensation N (t) or M (t).

The mode that the scale factor of this correction is used is identical with the mode of traditional scale factor of regulating transmitter power, and deriving from following formula draws:

P _TS=SL _TARGET+ I _RS+ α (L-L ₀)+L ₀+ constant value formula 1

Wherein, addition Item is represented multiplication factor, and unit is dB.As practical problem, the additional factor that is used for producing scale factor has become another simply at following formula, becomes in following formula:

P _TS=SIR _TARGET+ I _RS+ α (L-L ₀)+L ₀+ constant value+N (t)/M (t) formula 2

Wherein:

P _TSBe cell site's transmit power levels, unit is a decibel.

SIR _TARGETDetermine by receiving station.

I _RSInterference power level for receiving station.

L is the path loss estimated value of the nearest time slot in estimating path loss place, and unit is a decibel.

L ₀, the long-term average of path loss is the Continuous Observation mean value of path loss estimated value, unit is a decibel.

Constant value is a correction term.Constant value is used to revise poor between up link and the downlink channel, for example is used to compensate the poor of up link and downlink gain.In addition, if emission is receiving station's transmitting power reference level rather than actual emission power, then constant value can provide correction to it.

α is a weighted value, is the tolerance of estimating path loss quality, and the timeslot number between first communication time slot of the time slot of a preferably above path loss and cell site's emission is a foundation.The value of α is between 0 and 1.Generally speaking, if the time difference is less, the path loss estimated value is comparatively accurate, and α can be set at the value near 1.On the contrary, if the time difference is bigger, then the path loss estimated value may be inaccurate, and long-term average path loss value is likely the better estimated value of path loss.Therefore, α is set at one more near 1 value.Formula 3 and formula 4 are used for determining α.

α=1-(D-1)/(D _Max-1) formula 3

α=max{1-(D-1)/(D _Max-allows-1), the 0} formula 4

Wherein the D value is the timeslot number between the communication time slot of a last path loss estimated value time slot and first emission, is designated hereinafter simply as time-slot delay.If postponing is a time slot, then α is 1.D _MaxFor maximum possible postpones.It is 7 that the representative value of one frame of 15 time slots is arranged.If postpone to be D _Max, α is 0.If postpone greater than D _Max-allows, then can set α=0 and close open Loop Power control effectively.

Because rate N (t) and M (t) change at any time, the system shown in Figure 7 of invention compensates the variation of power demand, comes the offset data rate variation opposite with waiting for the target SIR by the definite revision of external loop-around.Like this, for open Loop Power control, in fact the present invention has eliminated the time period with the power in excess transmission that the factor that transmits causes according to rate variation.

As for closed-loop control system shown in Figure 4, because N (t) equals the M (t) under the static state, ignore the modification of fading channel or any variable interference, target SIR will be stabilized in a quiescent point, obtain the desired data quality.This situation is equivalent to single-rate shown in Figure 2 system.But in multichannel variable bit rate system, at certain time t, N and (or) M changes.As mentioned above, this situation can make the measured data quality metric improve, and the energy of emission is greater than the energy of actual needs.But actual measurement SIR does not change with the variation of N and M, because SIR records before the conversion under Eb/No (or SIR) increases following of repetition bits.Because external loop-around is with lower speed operation, in brief, the power control command that is sent back to transmitter is just no longer accurate.But external loop-around finally can detect the raising of signal quality, calculates a lower inner loop target SIR, as to being considered as the compensation of too high signal quality.When this thing happens, this low excessively target SIR will offset downward rising/decline decision, thereby reduce transmitter power.This point makes the signal quality at receiver place be lower than the desired signal quality conversely again.Final external loop-around can respond to the signal quality that descends with higher target SIR, and system will finally converge on correct power stage under static state.To this moment, received signal will no longer descend.

Figure 8 shows that the present invention is applied to the closed power control of variable how fast data, wherein corresponding element use with Fig. 4 in identical reference number mark.In the transmitter 51 of cell site 50, transducer 67 has an extra input 69 that is input to scale factor generation processor 55.This transducer provides a signal that is equal to  (N (t)/M (t)), and making processor 55 is the function of N (t)/M (t) by the scale factor of exporting 53 outputs, and it is described to contrast open cycle system shown in Figure 7 as mentioned.

In receiver, transducer 87 is to signal that is equal to N (t)/M (t) of combiner 88 (being preferably multiplier) output.The output of target SIR processor 74 is directed to combiner 88.Combiner 88 will merge from the rate variation data of transducer 87 and the target SIR data of from processor 77, export a target SIR through adjusting then and give combiner 76.

By this configuration, processor 77 is exported a nominal target SIR effectively.By the nominal target SIR that is applied to regard to coefficient N (t)/M (t) determine, change thereby make responding with compensation faster or regulating by the caused received power of changes in data rate by the measured signal quality.

Because rate N (t) and M (t) change at any time, system shown in Figure 8 compensates the variation of the expectation received signal intensity that transmitter power demand and receiver have changed, determines that the target SIR of revision comes the offset data rate variation opposite with waiting for by external loop-around.Like this, for open Loop Power control shown in Figure 8 system, shortened receiving the corrected signal factor and cause according to rate variation and be lower than the time period that allows quality.

Although the various assemblies of each cell site and receiving station mark separately, those skilled in the art can notice that various elements can merge.For example, the combiner 88 of system shown in Figure 8 can be included in the processor 74.Those skilled in the art can notice modification or the modification that other is consistent with the present invention.

Claims

1. wireless communication system that uses transmitting power control, user data is treated to a kind of multiple rate signal with rate N (t) in described wireless communication system, wherein N (t) is a time function, user data signal with rate N (t) is converted into a transmission of data signals with a very fast speed M (t) for transmission, and described transmitting power is to regulate with response rising/following drop data by using a scale factor, and described wireless communication system comprises:

At least one subscriber equipment, it comprises a user equipment transmitter, has:

One processor, its function with N (t)/M (t) calculates a scale factor;

One data signaling rate transducer, it converts the transmission of data signals with very fast speed M (t) to via repeating the user data signal that the selected data position will have rate N (t), thus in the transmission of data signals launched of increase energy per bit to the ratio of noise spectrum density; And

One combiner, it is in conjunction with scale factor that is calculated and the transmission of data signals that supplies described user device transmissions; And

At least one base station, it comprises a base station transmitter, has:

One processor, its function with N (t)/M (t) calculates a scale factor;

One combiner, it is in conjunction with scale factor that is calculated and the transmission of data signals that supplies described base station transmits.

2. system according to claim 1, the processor of wherein said user equipment transmitter is to calculate described scale factor according to the rising/following drop data and N (the t)/M (t) that are received from a base station, wherein said subscriber equipment transmits to described base station.

3. system according to claim 1, the processor of wherein said base station transmitter is to calculate described scale factor according to the rising/following drop data and N (the t)/M (t) that are received from a station, transmit to described subscriber equipment wherein said base station.

4. one kind is used for the method that wireless communication system controls transmitter power, user data is treated to a kind of multiple rate signal with rate N (t) in described wireless communication system, wherein N (t) is a time function, user data signal with rate N (t) is converted into a transmission of data signals with a very fast speed M (t) for transmission, and described transmitting power is controlled by using a scale factor, and described method comprises:

In at least one subscriber equipment:

The user data signal that will have rate N (t) via repeating the selected data position converts the transmission of data signals with very fast speed M (t) to, increases in the transmission of data signals of being launched energy per bit thus to the ratio of noise spectrum density;

Function with N (t)/M (t) calculates described scale factor; And

The scale factor that is calculated is combined with the transmission of data signals that supplies described user device transmissions; And

In at least one base station:

Function with N (t)/M (t) calculates described scale factor; And

The scale factor that is calculated is combined with the transmission of data signals that supplies described base station transmits.

5. method according to claim 4, wherein said scale factor are calculated according to being received from the rising/following drop data of a base station and N (t)/M (t), and wherein said subscriber equipment transmits to described base station.

6. method according to claim 4, wherein said scale factor are calculated according to being received from the rising/following drop data of a base station and N (t)/M (t), and transmit to described subscriber equipment wherein said base station.